Corn sizing apparatus



5 Sheets-Sheet l I g 74/ W WW1 \N\ H w v 3 Mm & .Q m

Filed Feb. 4. 1942 July 25; 1944.

H L JOHNSON CORN SIZING APPARATUS Filed Feb. 4; 1942 5 Sheets-Sheet 2 July 25, 1944. JOHNSON 2,354,376

I CORN SIZING APPARATUS Filed Feb. 4, 1942 SSheets-Sheet 3 H mvum'vto'r/ Aux L. JoQM-mm CMMM/V% H. 1.. JOHNSON 2,354,376

CORN SIZING APPARATUS Filed Feb. 4, 1942 5 Sheets-Sheet 4 July 25, 1944;

y 25,1944- H. L. JOHNSON 2,354,376

CORN SIZING APPARATUS Filed Feb. 4, 1942 5 Sheets-Sheet 5 Hum L. Joumcm Patented July 25, 194-4 I UNITED "STATES lATEN'T OFFICE r r a a ooms SIZING APPARATUS Harry L. J ohnson, Minneapolis, Minn. Application February 4, 1942, Serial No. 429,492 4 Claims. (01. 209316) This invention relates t improvements in apparatus for separating. corn and particularly to a means for separating hybrid seed corn into a plurality of closely and doubly dimensioned sizes tothereby facilitate planting operations.

.The primaryobjectof the invention ,is to pro .vide a machine embodying a plurality of vibrating screens apertured or reticu ated in 511 1 .m m her as to make almost any desired number of separations or groupings of the corn according .to width and to thickness dimensions and capable of..being set up andarracnged Vina compact assemblyto make all such separations in a single run. To this end the apparatus contemplates a screen arrangement such that two separate 'screensare arranged end to end in each layer, .or deck, of the machine one ,to make separations as .to width-and the other as to thickness and with means for separately classifying anddeliveringiat least four grades of corn from each layer .b'eing vibrated by the screensthemselves but in an opposite direction to thus carry the collected corn sizes towardthe head or receiving end of (the screens-Another and .related object is to provide .novelland efiective means for ilexiblysup porting the return pans from the screens to per.-

mil: such movements.

- A furtherobject is to provide novel and ef ective means for preventing the corn from piling up upon. the screens and for properly holding or :urging the corn kernels-into engagement with the :screens.

A further object is to provide by-pass means for distributing .thecorn tothe various screens and preventing .ove-rloadingof any one screen should the corn, as sometimes .occurs, be largely composed of kernels .of a certain size.

Still a further "object isto provide novel and effective Wipers or screen clearing means arranged to prevent lodgement of the corn kernels .in the perforations of the screen and with novel operating and connecting means for th Wipers to permit convenient removal and replacement of the screens when setting up the apparatusto size specifications.

These and othermore detailed and specific ob- :jects will be disclosed in the course of t f ll ..ing specification, reference being had to the acc,ompanying drawings, in Which- Fi i side elevation 9f m or -i si i a paratus an up er scr en ein hQWn a a tially pulled out endwise in process of removal.

Fi 2 i a .ireem iii horizonta se iie view a on th e ,2-2 in F s owin he .tieem clienlsm icr the screen Wiper Fi a oneiiusl nal er ica sestic th ou h meannessls..-

Fi s i a enlarged v ieeiunitaryiiirs e i v .vl iv er" th ad ac nt spaces ips secs 9? ihe Wiper actua in hers.- g. I Fi .5 is enl r e iraei ie l ar s de elf-Ya tion, pa tially long tud nal and ve t ca s ..tion. .of an upper e d por ion o t e a par tu .Fi 6 .i a view aken alon t i e -5 in .Fig. 5.. v

Fi '1 i a p an View o the ap aratus e feed ho pe b in removedi 8 is enlar d inve te lan or t pm i w el n s en an a ra me t o h next- Fie, .9 is a fragmenta y v tica cro s secil a l view throu h eceiving end ort enso the s reens showing the byeness o dist ibutin mean .50?

thecorn. I r

Fig. 10 isa vert al lon itudina sct enal iew a o 1 1 111 3ID'TJQiIlFiQ-Q- Fig. 1.1 is aplan view f ame d .ncrilgii of the screens of Figs. 9 and 10.

Fi 12 is an enl r e p es section th ou one of the sc een winersior wiper barsvReifemng .ncwmore par cularly and by re e .ence characters to the. drawin s, my. imp oved apparatus comprises, a mountin n. up g iih frame .havingzbase memb rs 1, Set Pa alle relation to which are secured up i h hearin mb s U in spaced oppositel al gne pa r of iced bye slidi g s l moved h o e th medium 9 es le i '21." tu n d-Wil e w el 1 and carrying at least one gear 22 meshing with ia rack 23 on the gate (see Figs. 1 and 5).

. ih she is i ar re e te a d the en apparatus operated by a suitable prime mover .such as an electric motorj l which as hereshown is connected by a belt 25 to a pulley 2.6 on'one extended end of shaft l3, the belt being kept taut by arranging the motor on a base 2] pivoted at 28 to the base members LO-jas clearly shown in Fig. 1. The shafts I 3-14 are connected by sprockets 29 and chain 30 at one end and this drive connection is enclosed within a guard housing 3|. The shaft [3, which may be termed the main or driving shaft, also carries a small pulley 32 over which is trained a belt 33 driving a large pulley 34 on a countershaft 35 journaled in bearing brackets 36 on the side posts 15. A smaller pulley 31 on countershaft 35 in turn drives a belt 3| over a larger pulley 39 on a crankshaft or wiper drive shaft 40 which is journaled in bearing brackets 4| secured to the base members I. is rotated much slower than shafts I3l4 by virtue of the speed reduction afforded by this arrangement but obviously other driving means, such as sprockets or gears, may be used if desired. The function of the various shafts will presently appear.

The side posts 15 are braced by angularly extending bars 42 secured between their upper portions and tie bars 43 which join the bearing members ll.

The screen assembly or screen mechanism is supported above the frame thus described and in the embodiment here shown has three screen layers or decks comprising stacked shoes designated generally at 4344 and 45, although more or less than three of such elements may be used as may be desired and according to the number of sizes or classifications of the corn required. Each shoe is spaced from the one next beneath and parallel thereto and they are secured in such relation between spaced pairs of uprights or tie members 46-4! which at lower ends extend loosely between the upper ends of the members H with which they are substantially vertically aligned. These lower ends of the uprights 45-41 carry bearings 48 which engage eccentrics 49 carried by the shafts l3 and I4 and by such mounting not only are the screen shoes supported but they are also given a rotary, vibratory movement by the eccentrics at a frequency dependent upon the motor speed and ratio of the drive between the motor and shaft It. The individual shoes are further connected by angularly extending braces-50 as seen in Fig. 1 to operate as a unit. 1 r i r The construction of the'shoes 43, 44 and 45 difier in only minor details and a description of one will accordingly sufiice for all. Each shoe comprises a pair of side frames having medial, longitudinally extending and outwardly pressed ribs 52 which not only stiffen them but also provide interior channels 53 to slidably receive the edges of the screens as will presently appear. Upper margins of these side frames 5| are outwardly flanged as at 54 while lower margins have inwardly turned flanges 55. The shoes slope somewhat from what may be termed theirheads or receiving ends (beneath the feed hopper l6) toward their tails or delivery ends and the uppermost shoe is arranged beneath the hopper so that the corn fed from the opening l8 therein will fall upon the head of the screen therein. However, and this is important, the shoes by the Very nature of their operation and construction need have but little, if any, slope or inclination since the corn, as has been found in practice, will progress along the screens without the necessity of sloping the screens. Ob-

viously the vertical height of the apparatus may thus be held down resulting in a very desirable compactness.

The crankshaft 40 of course.

On each of the uppermost two shoes 43 and 44 ranged lengthwise in the plate.

the lower flanges 55, from about the longitudinal centers of each shoe to its tail end, are joined by a bottom plate 56 which closes substantially one-half of the bottom of each shoe and has an upwardly turned forward end 51 clearing the channels 53. From this flanged end 5'! forward, or to the head end of each of these shoes, the bottom is then open as designated at 58. On the contrary, the lowermost shoe 45 is closed by a bottom 56 throughout its length as seen in Fig. 3. However the shoes each have in their respective bottom plates 56 and 56 a pair of transversely extending discharge openings or slots designated at 5960 for shoe 43, 5950 for shoe 44, and 55 60 for lower shoe 45, and in addition the latter has a third similar slot or opening 5|. The slots 59, 59 and 59 are located about midway between the longitudinal centers of the shoes and their tail ends while the slots 60, 60 and 60 are located immediately at said ends. The slot 6| on the other hand is located at about the center of the lower shoe as clearly shown in Fig. 3. Beneath each slot a transversely extending and sloping discharge duct 52 is provided having a lateral spout 63 for the attachment thereto of a flexible tube or conduit (not shown) for leading off the corn discharged at the various slots.

Also at the tail ends of the shoes transversely extending and sloping discharge ducts 64, 55 and 66 are arranged and having openings 61 in their sides adjacent said ends. Said ducts also have spouts 68 similar to those previously described.

Adjacent the slots 59, 59 and 59 the bottoms 56 also have upwardly turned ends, or balfles, 69 the purpose of which is to guide the corn into the slots and into the ducts 62 adjacent thereto as will presently appear.

Each shoe 43, 44 and 45 carries a pair of screens arranged end to end therein and here again, since the screens for the various shoes are identical except as to the sizes of their respective openings, a description of one pair of screens will sufiice for all. The screens for each shoe are designated generally at 10 and H and each comprises a rectangular frame having sides 1!, ends I3 and a medially located transverse brace bar or cross piece 14. Each screen frame is covered by a flat screen plate 15 which is secured at its margins thereto and in one screen ID the openings 16 are round while in the other Tl the openings are in the form of narrow slots ll ar- The width of the screens, and the vertical thickness of the frame sides 12, are such that the screens may be readily slid one at a time endwise into the shoes with the sides slidably received in the channels 53. The screens are thus inserted from the head ends of the shoes as will be evident and that they will, when thus arranged end to end,

fill the shoes lengthwise and the screens last inserted are provided with face plates 18 across their ends designed to close the head ends of the shoes as best seen in Figs. 5 and 6. Studs 18 welded, orothe-rwise secured, to the shoes enter openings in these face plates 18 as the screens are pushed home and wing nuts 8| may then described. the seed corn; :of heterogeneous sizes, is of course placed in the'ihopper I56 from which it be turned up on these studs to lock the screens in'the shoes. The face platesalsohave han'dles 82 .to facilitate insertion and removal of vthe shoes, drawer fashion, into and out of the shoes.

Return pans83-84 are arranged-beneath the r upper two shoes 13 and 44 and, more specifically,

is fedat a suitable rate; controlled by manipulating the hand wheel'..2I-, :to fall upon. thel-head below the bottcmopenings 58 therein, said pa'ris and are closed at their higher or receiving 'en'ds' B'I-Ebut open at their lowendischarge ends 88;

Substantially above each end portion'of each pan 83-84 a hanger member or angle bar 89 is secured across the flanges 54 of the respective shoes 43- there being thus four of such memfbers and all of them having their ends extended well beyond the sides of the shoes as best shown in Fig. -6. Similarly arrangedand mountedhang er members, or angle bars ilfiare secured'across upper marginsof the pans. Between the extend ed ends of these members 89% flexible hanger strips 9! of rubber or similar material ares-ecured, as by means of screws 92, and said strips are'arranged between each lower portion of the pans upwardly to, the-members 89 --thereabove in order thus to support thepansbeneath the respective'shoes. Obviously, while the strips-9! will support the pans against downward displacement, they will permit the pans to swing or oscillate freely beneath the shoes 'ands'uch movements will necessarily'be in a lengthwise direction with respect to the shoesysincethe strips 91 are disposed with their wider dimensions extended transversely tothe pans and'shoes as clearlyshown. H

The'hanger members 90 on thepans 83- 84 nearest'th eir higher ends '3? are extended-beyond the strips 96, as seen in "Figf'fifand are rigidly "connected secured at 9 to these extended ends. To these jmeinbersfii at each side of the machinefilink bars 95 are pivoted, as at 9B, and extend "there- "from toward the side posts '55 near' which they "are pivoted at 9'! to the upper ends of rockerbars $8 fulcrumed intermediate their en'dsat 99 upon brackets illi) 'afiixed to said posts. Link bars fllll are then. pivoted at I82 tdlowe'r ends of the 'rockerbars 98 and extend back beneath the; link bars95',being pivotedat I03 to the upright side members 46 as shown in Fig. l. The foregoing "arrangement'is such thatthe oscillating 'motion of the screen assemblywill rcckt'he bars "93 on 'their' pivots 99 through action of the lowerlink fbars MI; and such' rocking motion will be trans-' "initt'ed'to the return pans 83 andfi l' by the'upper link bars 95. However, the movement of the screen' assembly will be translated to an'oppo site movement of the return pans causing the pans to by upright 1 tie' members-"53" shift horizontally and endwisein one direction as the screen shoes'move in the opposite direction, as should be readily apparent.

The discharge ends 88'ofthe return pans 83 -84 enter loosely between the upstanding'sides 1'04 fof guard 'memibers between the shoes, said sides 'b eing'turn'ed' from the lateral margins of'transverse, upright plates H15 secured b'y'base flanges 10 6 and upper margins I01 between the'sho'es" as jclearly' shown'. Such guards are o'fhcours'e' for thepurpose of preventing the corn falling from 'the pans from flying oh" the sides or, ends of the shoes. For a similar reason the uppermost" shoe carries a narrow upstanding 'guardflange I08 around its's'ides and end-beneath the hopper H5.

"""Inthe" operation of'the machine ast-hus" 'far of the screen .10 in the uppermost shoe 43. The

motor 24 being then in operation the entire screen assembly is given a vibratory action in'which there is a vertioalcomponent such that the. corn kernels upon'thesoreens 'lfie-e'llmwill lbe tossed upwardly to fall back and either pass. through, or be rejected by, the openings l 3'-l'l:therein.- -'As is well known in the art the two important dimensions in corngfor seeding purposes. are the width and thi'cknessfof the kernels and theround openings or holes 16 will, in :well known manner,

size the kernels as to width while the slotted openings Ttwillsize as to thickness. The screens are of course setup with regard to the sizeof their respective openings to pass successivelysmaller -kern'e1s in *both dimensions as they progress "downwardly from shoe to shoe.

Considering first the operation of "the uppermost shoe 33, in which screens having the largest openings are usually arranged, it willb-e evident that/the corn falling from the hopper "willfirst be sized as to width, the throughs or kernels passing remainder of the screen and "the. larger width sized kernels or throughs from-the-larger'slots will obviously fall through slot tad-into the duct 62 for separate collection. Corn kernels passing through the narrower slots in the remainder of the screen then flow through the slot fill-ior another and separate collection. Rejected'kernels from-both screens will fall into the end duct 64 and this oversize corn may be used as reserve or discarded for seeding purposes.

The corn' falling into the uppermost return pan 83 is carried back to the head of the screen mechanism and delivered upon the screen "min shoe M, being then subjected to anotherwidth sizing by the round holes 75 therein and the throughs falling into the next lower return pan 84." The rejects or overs from this width sizing are then subjected to two thickness sizings upo n the. screen Ti'in shoe and the throughs'are separately delivered through the slots 59 -6B as doubly dimensioned seed classifications. The rejects from this shoe are then delivered through duct 65.

In similar manner the corn falling from the return pan 84 is sized as to width by the screen 10 in the lowermost "shoe 45 and the throughs are, in this case of useless small sizes, delivered through slot 6| and duct 62 for separate collection. The corn rejected by screen it is then doubly sizedas to thickness by screen "H with the two sizes delivered" from slots 55* and 66 while the oversize or rejects are delivered by ductBS. It will be noted that the rejects or culls from ductEZ have only been sized as to 'width and this culling operation therefore does not reduce the capacity of the slottedscreens. From the foregoing-"it will be evident thatby acontinuous, single run operation noless than twelve separate classifications of corn are secured, four from each shoe,- and obviously additional shoes may be arranged in the mechanism to secure further classifications if desired. The flow and screen arrangement is further such that no doubling up or duplicate sizings of the same corn are carried out. The screens may be readily removedand others substituted having openings of any size according to the grades of corn required.

To assist in proper engagement between the corn kernels and screens aprons I09 of cloth or flexible sheet material may be laid over the screens 'I0II in any shoe, such aprons being here shown as arranged only on the upper shoe 43. These aprons are fastened at one end around bars H action I provide loose beater rods or fingers III which are connected at one end by chains or similar light flexiblemembers H2 to the hanger member 89 nearest the head end of the shoe totrail ofi loosely toward the tail of the screen.

These rods will bounce about as the screen mechanism vibrates, effectively breaking up any concentrations or piles of corn which may tend to collect.

Wire fingers I I3 (Fig. 5) may be secured to the uppermost hanger member 89 near the hopper I6 an extended through the feed opening I8 up into the corn. Since these fingers will then vibrate with the screening mechanism they will stir and agitate the corn in the hopper to iacilitate proper feeding action.

There is some tendency in machines of this nature for corn kernels to become lodged in the openings in the screens and to dislodge such kernels I provide the following mechanism. Beneath each screen I0'II there is extended a pair of longitudinal guide strips H4 parallel to and adjacent the frame sides I2, being secured at their ends at H5 to the frame ends as seen in Fig. 8. Two carrier bars II 6 are extended transversely between the guide strips I I4 with the ends notched and slidably engaging upper sides of the strips and such bars H6 are connectedv and held in parallel relation by brace strips II'I secured therebetween. Flat operating bars H8 are slidab-ly arranged lengthwise and centrally beneath each screen and are secured at H9 to the carrier bars H 8 so that by reciprocating said operating bars the carrier members will be moved back and forth beneath the screens. For each carrier bar II'E two screen wiper bars or strips screens I I, which are first inserted into the shoes, have their ends H3 extended beneath .the tail ends of screens I0 and these ends hav apertures I (Fig. 4) to receive pins I26 secured to the adjacent ends of the bars beneath said screens III. In inserting the screens the pins I2'Ii are engaged in the openings I25 and the wipers on each pair of screens will then operate as a unit. Also such connection causes the screens II to be pulled out in the shoes so that they may be reached and released when the screens I0 are withdrawn from the shoes as will be understood.

The ends of the operating bars H8 nearest the heads of the screens have attached thereto, by pivots I2I, the links I28 which extend loosely outward through the face plates 18, which are slotted at I29 for this purpose, and these links areupwardly supported and guided when the screens are in operative position 'by angles I30 secured across the ends of the side members SI of the shoes. An upright rocker shaft I3I is journaled in bearing brackets I32 secured to one side post I5 and at spaced points this shaft carries radially extending arms I33 which extend at their ends toward the ends of the links I28. Both the arms I33 and the links I28 are apertured at their ends to pivotally receive connecting pins I34 which are detachably held in engaged position with these parts by latches I35 pivoted beneath the arms at I38 and having notches I31 to engage peripheral grooves I38 in said pins. When said latches are swung aside (Fig. 7) the pins may be upwardly removed.

Adjacent its lower end the rocker shaft I3I carries a crank arm I39 which is connected to one end of a connecting rod I40 which operates at its other end on a crank or eccentric I4I on the shaft 40 and as said shaft rotates slowly, in the manner described, it is evident that the rocker shaft will be oscillated about its vertical axis. Such operation will swing the arms I33 back and forth in the horizontal plane toward and away from the shoes and will accordingly slowly reciprocate the wiper operating bars H8 beneath each screen in the desired manner.

When removing the screens the pins I34 are removed as described after which the screens may be readily pulled clear of the shoes. The pins are I20 are provided and leaf springs I2I secured between their ends at I22 to upper sides of the bars H6 are extended endwise and secured at I23 to the wipers I20 to hold them parallel with the carriers and transversely to the screens.

The operating bars I I8 for the wiperson theja then of course replaced when new screens are put in place.

It sometimes occurs, due perhaps to unusual soil and growing condition in a seed corn growing area, that by far the larger part of the corn is of a certain width instead of widely varying in this dimension as is the usual case. When the sizing apparatus is used under such conditions there is obviously a tendency of the round holed screens to flood with corn since the greater share of the corn will pass a certain size of opening. To overcome this flooding tendency I employ the by-pass means shown in Figs. 9, l0 and 11.

The screen I0 in an upper shoe is provided at its head or receiving end with transversely spaced openings I42 which in their aggregate width, crosswise of the screen, equal substantially one half the total width of the screen. The screen III in the next shoe below (having sizing openings of the same diameter) then has center and side openings I43 which fall in the vertical plane between and outwardly of the openings I42 and also aggregate in width about one half the width di mension of this screen.

The by-pass means, per se, is substituted for the guard I04--I05 between the shoes carrying the screens thus apertured and comprises a back plate or supporting plate I44 secured at its upper edge I45 to the upper shoe and by its base flange I45 to the next lower shoe. Funnel-like chutes I41 are secured to this plate I44 and taper downwardly at sides and inner ends from their upper to their lower ends, both ends being open. As best seen in Fig. 10 the upper ends I48 of these chutes are well adapted to receive corn kernels falling through the openings I42 while the lower ends I49 are disposed above the closed portions I50 of the screen between the center and side openings I43 to guide these kernels downwardly .onto that screen. Guide wings II having laterally sloping surfaces I52 are arranged at the lower, inner sides of the chutes I41 immediately beneath the discharge end I53 of the return pan I54. The plate I44 may have sides I55 extended inwardly to guard against the lateral escape of grain. Up-

standing wall or partition members I56 are secured to the screens along lateral margins of the openings I42-and I43.

In operation about one half of the corn feeding upon the screen having the openings I42 will now be handled by that screen and the remaining part will fall directly through the openings I42 and then down through the chutes I41 and upon the closed areas I50 between the openings I43, being then sized by this screen, and thus splitting the corn evenly between these two screens. The corn passing through the uppermost screen I0 (through its sizing openings) and falling into return pan I54 will fall therefrom onto the guide wings I5I and will be guided by the sloping surfaces I52 thereof outwardly to fall through the openings I43 and directly down to the screen I0 next below, to prevent repeat sizing. Thus it will be seen that each screen will handle a part of the corn and no single screen can possibly be flooded as would be the case if the majority of the corn passed the upper screen and fall directly to the one next below, along with the sized corn from the pan I54.

The purpose of staggering the openings I42I43 as described and shown is of course to spread the streams of corn evenly over the head ends of the screen and utilize the full width of the screens. The partitions prevent comingling of the various streams of corn.

To prevent corn sized by the shoe next above the screen having the openings I42 from falling directly through these openings, I may arrange a baffle l5! toguide the corn into the adjacent return pan as seen in Fig. 10, supporting said baffle from one of the cross plates I05. However in the three shoe machine the hopper will of course feed the upper screen shown in Fig. 9 and such bafile may not be used.

It is understood thatsuitable modifications may be made in the structure as disclosed, provided such modifications come within the spirit and scope of the appended claims. Having now therefore fully illustrated and described my invention, what I claim to be new and desire to protect by Letters Patent is:

1. In a. corn sizing apparatus having a plurality of superimposed screens arranged to receive corn at one end and progress said corn toward the other end while making size classifications thereof, one screen having openings adjacent its receiving end to pass a portion of the corn directly downward without sizing, means for collecting corn sized by this screen, the screen next below having openings to pass this sized corn from the said collecting means directly down to a second lower screen, and guide members disposed on the screen beneath said collecting means between the openings in that screen, the said guide members having laterally sloping portions for guiding corn flowing from the collecting means downwardly through said openings.

2. In a corn sizing apparatus having a plurality of superimposed screens adapted to receive the corn at one end and progress it toward the other end while making size classifications thereof, a first screen having openings in its receivlng end for passing a part of the corn directly downward to the second screen, chute members disposed beneath the first screen for delivering the corn passed through the openings therein to the second screen, the said second screen also havin openings in its receiving end and these openings being offset from vertical planes passing through the corresponding openings in the first screen, means for collecting and guiding the corn passing through the first screen into and through the openings in the second screen, and a third screen arranged beneath the second screen for receiving the corn passed through the openings therein.

3. ma corn sizing machine, a hopper, a series of superimposed vibratory screens arranged to receive corn at one end and progress said corn toward the other end while making size classifications thereof, two upper screens of the series having identically sized classifying openings, and a third, lower screen, having relatively smaller classification openings, means for dividing a supply of corn discharged from the hopper into two parts and respectively conducting such parts to the receiving ends of the said two upper screens whereby said two screens will perform identical functions in classifying the corn supplied thereto, and means for directing the corn passing through both of said screens onto the third mentioned screen for reclassification by the relatively smaller openings therein.

4. In a corn sizing machine, a series of vibratory screens having round and slotted openings for the width and thickness classification of corn as the same is passed thereover, two of such screens having round openings of identical size so as to reject corn of like minimum widths on both screens, a third screen having round openings smaller in size than those of the said two screens, means for supplying a continuous flow of unsized corn, means for dividing such flow of corn into parts and directing such parts to said two screens for similar classification thereby, and.

means for directing the corn passing through both of said two screens in a reunited flow over the third screen for classification thereby.

HARRY L. JOHNSON. 

